Multi-gap gas switch for the electromagnetically driven experimental facility CQ-7

In this paper, a six-stage switch for the electro-magnetically driven experimental facility CQ-7 is developed. The switch is 131 mm tall with a radius of 108 mm, the total gap is 36 mm, and the inductance of the switch is about 40 nH. The simulation of the electric field strength between the electrodes shows that the electric field is uniformly distributed with the non-uniform coefficient 1.14. The characteristic experiment studies of the switch show that, when the switch work with the voltage in plus or minus 100 kV, the peak current is 70 kA, the switch breakdown delay time and jitter are 35 ns and 3 ns respectively. Analyzed by Gaussian function, the self-breakdown probability is less than 110-4 when the switch work with the safety coefficient 80%. The switch can meet the requirements of the development of the electro-magnetically driven experimental facility CQ-7.